Hey, thanks for your suggestions!
We already have a co-op mode, but it's still in alpha testing mode. It most likely will be in Early Access from the start.
Multiplayer is something we really want to do, but takes some planning and time, so it isn't our focus currently. So this will be more like an update once the final version is released.
Co-op mode integration and networking is based on BeRo's RNL, which is also FOSS: